An investigation has begun after a "confused gentleman" picked up the wrong kid. Picture: ThinkstockSource: Supplied

IT'S every parent's worst nightmare.

An investigation has been launched after the wrong child was handed over to an older man who came to collect his granddaughter from school for a doctor's appointment, reports The Guardian.

The six-year-old girl shares the same first name as the man's granddaughter and is in the same year. She accompanied the man on a bus from Gillingham's Napier primary school in Kent, UK, to the doctor. She was prescribed paracetamol and was dropped back to class.

The girl's family only heard about the incident when she came home and showed the medicine to her mother.

"I went ballistic. I was boiling inside," said the girl's father, who took her back to the medical clinic to check she had not invented the story. "The first thing I thought was the worst. I had to ask my daughter the sort of questions no parent ever wants to ask: 'Did he do this, did he do that?'"

"When your daughter has been walked round town and taken on a bus by a strange man, it makes you sick to the stomach. It's every parent's worst nightmare. Everyone knows to tell their children not to go with strangers, but I want to tell every parent in that school - tell them again tonight.

"Thank God it was an innocent thing done by a confused old gentleman."

The school's principal said all procedures relating to student safety were being reviewed as part of the investigation.

"I have also spoken with the mother of this child to offer our sincere apologies over this regrettable incident and to assure her that we are reviewing all our safeguarding policies - with the help of the council - to ensure this never happens again" she said.

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